Hydraulic jack



Oct. 4, 1932. H. w. BOLENS HYDRAULIC JACK 2 Sheets-Sheet 1 Filed April2, 1928 Oct. 4, 1932- H. w. BOLENS HYDRAULI C JACK 2 Sheets-Sheet 2Filed April 2, 1928 INVENTOR.

A TTORNEY.

Patented oee 4, 1932 may w. non-ans, or mar wasrrmo'rox, vnsooram KHYDRAULIC JACK Application ma April 2,1988. Serial 10.288385.

This invention relates to an im rovement in hydraulic jacks especially,alt oughnot Along with this advantage the lifting mech- 1 anism is so.constructed and so organized with the jack as to have little or nooverturning moment whereby the jack possesses a very high stability.

Another object of the invention resides 1n the provision of a hydraulicjack of thisv character of the type having hydraulically operablelifting mechanism and a handle connected thereto and carrying the pumpfor actuating the lift mechanism and wherein provision is made forpreventing ingress of any appreciable quantity of the oil or otheroperating fluid employed into the handle and for draining from thehandle any oil that may find its way thereinto.

Another object is to provide a hydraulic jack of this character havingnovel knockdown operating mechanism for the pump which multiplies thepower applied to the pump and to the jack to facilitate the lifting ofheavy objects such as heavy motor trucks or the like and yet is foldableinto a compact space so as to be conveniently stored in the tool box ofthe vehicle, under a seat thereof, or in a similar place.

A further object of the invention is to provide a hydraulic jack havingthese advantages and capacities and which isof simple 'and durableconstruction, reliable and efiective in operation, and easy andcomparatively inexpensive to manufacture. 46 Other objects andadvantages reside in certain novel features of the construction, ar-

rangement and combination. of parts which will be hereinafter more fullydescribed and particularly pointed out in the appended ,claims,andreference being had to the accompanying drawings forming a part of thisspecification, and-in which:

Figure 1 is a view in side elevation showing a hydraulic jack.constructed in accordance with the present invention;

Figure 2 is a fragmentary view in side elevation showing another type ofhandle and operating means that may be employed for the pump of thejack;

Figure 3 is a view in horizontal section taken on line 3-3 of Fi re 1;

Figure 4 is a detalview in section taken on line 4-4 of Figure 1;

Figure 5 is a view taken partly in section on line 5-5 of Figure 3, buthaving a num ber of the elements of the jack shown partly or wholly inelevation for the sake of simplicity in illustration;

Figure 6- is a detail view of the operating lever of Figure 1, the leverand associated 7 parts being shown in top plan;

Figure 7 is a view taken on line 7-7 of Figure 3, parts being brokenaway and parts being shown in elevation for the sake of simplicity inillustration, the handle in Figure :5 7 being swung up to avertical-position;

Figure 8 is a somewhat enlarged view in transverse vertical sectiontaken in the plane of line 88 of Figure 7; and

Figure 9 is a fragmentary detail sectional view similar to Figure 8 butshowing a different position'of the parts to illustrate the action ofthe trip rod in unseating the valves and in blocking the opening in themounting member. c

Referring to the drawings, it will be seen that a hydraulic jackembodying the present mventioncomprises a base 1 carryin thehydraulicall operable lift mechanism esignated genera ly at 2 and also aswivelled handle {5 clgntaming the pump 4 for operating the ac v I Thehydraulically operable lift mechanism includes an inner or jack cylinder5 having its lower. end threaded into a recess provided therefor in thebase 1 as indicated at 6 -(see Figure 7). Surrounding the inner cylinder5 andm spaced relation thereto is an outer or reservoir cyhnder 7 havingits lower end bevelled and ground or machined to engage and box 14provided in the head 9.

Lifting means is carried by the rod 13 of the piston 12 and may includea lift screw 15 engaged in a threaded socket 155 provided in the upperend of the piston rod (see Figure 5). The upper endof the lift screw isreduced and releasably secured as at 16 to a lifting shoe 17. While theshoe 17 may be taken off for purposes of assembly and disassemblypreferably it is rigidly secured to the upper end of the screw 15 whenthe jack is in use. By turning this shoe 17 the screw 15' may berotated-in its threadedbearing 15' and caused to project above the upperend of the piston rod 13 to the extent necessary for engaging relativelyhigh objects. By turning the screw 15 to cause it to move down into thesocket of the piston rod 13 the shoe 17 is appropriately lowered.

The lifting mechanism also includes an inverted U-shaped supporting bardesignated generally, at 18. and having a body portion 19 and downwardlyextending parallel legs 20 integral with the ends of the body portion 19and located adjacent diametrically opposite portions of the cylinders 5and 7. The lower end of the le 20 are connected by a rim 20" which sliably embraces the cylinder and aids in maintaining the legs 20 parallelto the axis of the cylinder. The body portion 19 is formed with acentral opemng 21 I counter-sunk around its lower end'as at 22 toreceive and ,abut against the upper end of the piston rod 13. The screw15 passes loosely through the openin 21. If desired, the bod portion 19may appropriately fastene to the piston rod 13 but the interfittingabutting relation described and shown in Figures 5 and '7, together withthe action of retractile coil sprin 2 3 with which the jack is providedis sufliclent to maintain these parts properly assembled. As illustratedin igures 1, 5 and 7, the springs 23 have their upper ends connected topins 24 ri 'd with the body portion 19 and projecting literallytherefrom. The lower ends: of the springs 23 are connected withapertured ears 25 integral withthe base 1. These springs are undertension when the piston 12 is in it's lowermost position in the cylinder'5 and so operate to forcethe body'portion 19 of the sup.- porting bar18 down onto the piston rod 13.

he primary function of these springs, however, is to automa'ticallretract or lower the lifting mechanism an piston 12when the 1,aso,7aa

fluid below the iston is permitted to flow out from beneath t e same.

- Each leg 20 isprovided with a vertical 'series of teeth 26 and with alengthwise shoulder or guide 27-behind the teeth 26 (see Figures 1 and3). An adjustablelifting lug 28 is provided and has a portion 29 soshaped and serrated as to be adapted to engage the axle or other part ofan automobile or other similar motor vehicle. This lug 28 is alsoprovided with a pair of supporting fingers 30 and a pair of retaininghooks 31, there being one supporting finger-for each series of teeth 26and one retainin hook for each shoulder 27. Each finger30 ears on aselected tooth 26 and each retaining hook 31 engagesa portion of itsshoulder 27 adjacent the tooth 26 engaged by the finger 30. When a loadis placed on the lug 28 the lug tends to rock on the fingers 30 engagedby the teeth 26 but this rocking tendency is counteracted by the hooks31. A consideration of this action and an inspection of Figure 1 of thedrawings will make it clear that the fingers 30 exert a lateral orhorizontal thrust to the right, as viewed in Figure 1, while the hooks31 exert a lateral or horizontal thrust toward the left in Figure 1.While the lug 28 may be supported in a horizontal position preferably itis designed tobe angled slightly upwardly and outwardly from the le' s20 when it is supported on an of the test of the legs. The ug is locateentirely within the outline or confines of the base. In other words, aperpendicular dropped from the outer extremity of the lugwould'intersect the base as will be understood from Figures 1 and 3.This is made possible by the construction whereby the lug partiallyembraces the cylinder and is engaged with supporting means locatedmid-way between the ends of the base. With the lug 28 so supported onthe base the jack has a very low overturning moment and thus has markedstability so that even very heavy loads applied on the lug 29 do nottend to tilt or overturn the jack.

At one end of the base a pair of lugs designated at 35 and 36 isprovlded(see Figures 3, 8 and 9). On these In a swingable mountin memberdesignate generally at 37 is swivel ed or ivoted for movement about ahorizontal axis. This mounting member carries the pump,4 and theoperating and member 37 therein and receiving theadjacent end portionsof 1 trunnions' 40 and 41, respectively.- The trunnion 41 also has aportion received in a recess 42 provided in the lug 36 and suitablewashers 43 are provided between the ends of the trunnion 41 and the rein which it is fitted. The trunnion 40 has a portion there of fitted foraxial adjustment in an en- I ing 44 formed in the lug35. Axial ad ust-Iiient of the trunnion 40 is'efiectedby a foljusted position by means ofa lock nut 49 threadedly connected withthe, lug 35 and. bearing againsta washer 'interposed between the lock nut and the follower. With thisconstruction the connectin member 1s swivelled on the jack base but t 1eswivelled connection may be sufliciently tight to hold.

the connection member against accidental displacement in any an laradjustment and of course is entirely Oll tight.

The hand operated pump 4 (see Figures 7 and 8) comprises 'a pump barrel52-the lower end of. which is threaded into the connectin g member 37 asindicated at. 53. A plunger 54 is operatively fitted in the barrel 52and is carried at the lower end of a plunger rod 55. The pump isenclosed in a combined housing and tubular handle section 56 alsothreadedly connected with the member 37 as indicated at 57. The upperendof this housing section 56 is closed by a packing arrangement 58through which the plunger rod is slidably fitted. Above the packing 58the combined housing and handle is reduced and I consists ofa smallertubular section 59, the

lower end of which has a releasable'threaded connection with a couplingmember 60 threaded into the lower housing section 56. This housing soconstituted serves to encase the pump and its controls and also providesa handle for regulating the angular position of the pump.- The upper endportion of the plunger rod 55 is always above the packing '58 and isthreaded into a combined coupling and guide 61 which has a socket 62receiving a ball 63 carried at the lower end of an operating rod 64,slidably fitted in and projecting exteriorly of a bearing 65 in thehousing section 59. The coupling 61 it provided with an entrance slot 67to its socket 62 to permit of the assembly and disassembly of the ball63 therewith. With this construction when the section 59 is unthreadedfrom the coupling 60 and the socket member 61 pulled out beyond thecoupling60 the operating rod 64 and the section 59 may be tilted over tothe side and the ball 63 pulled out of the socket 62. I

The lower end of the pump barrel 52 freely communicates through a port 70' with an intermediate portion of a-transverse passage 71 extendingthrough the connecting member 37 and communicating at one end with'aport 72 in the trunnion 41. The port 72 communicates through a thimblescreen 73 with a passage 74 extendingaxially through the lug 36 and inopen communication with an inclined, assage 75 extending at an anglethrough t e lug 36 and base 1 and terminating at the bottom of the s ace75 between the cylinders 5 and 7 whic provides a reservoir for the oilor other operating fluid employed (see Figure 7). The reservoir 7 5communicates through a passage 76 in the cylinder head 9 with theinterior of the upper end of the cylinder 5 above the iston 12.

The other end of the passage 1 communi cates through a thimble screen 78with a port 79 provided .in the trunnion 40 and communicating with anaxial passage 80 in the follower 45. The passage 80 communicates throughradial ports 81 with an external annular groove 82 formed in theperiphery of the follower 45 and sufliciently wide to be incommunication in any adjustment of the follower with a passage 83extending through the lug 35 and the base 1 into the space in thecylinder 5 below the piston 12.

The communication between one end of the passage 71 and the reservoir 75" and the upper end of the cylinder 5 is controlled by an intake ballvalve 85 coacting with a seat 86 provided in the passage 71, the ballvalve being held against its seat by means of a spider 87 slidablyfitted in the passage 71 and having a 71. -'A coil spring 90 isinterposed between the spiders87 and 89 and forces the spider 87 againstthe ball valve 85 and in turn forces.

the ball valve 85 against its seat 86. The pin 88 terminates in slightlyspaced relation to a discharge ball valve 91 which coacts with a seatprovided therefor around the port 79 of the trunnion 40 to controlcommunication between'the other end of the passage and the lower end ofthe cylinder 5. A coil spring 92 engages the valve 91 to hold it againstits seat. v

To provide for the release or unseating of the valves 85 and 91, a triprod 95 is'provided and has its lower end slidabl fitted in alongitudinal opening 96 forme in the connecting member 37, intersectingthe passage 71 andlocated on the side of intake valve 85 remote from thepump 4 (see Figures 8 and 9) j The lower portion of this trip rod 95 isformed with a cam or inclined surface 97 positioned to en gage andunseat the ball valve 85 when the trip-rod 95 is raised. When the ballvalve 85 is unseated, it displaces the spider 87 and the pin 88 to theleft as viewed i in Figure 8 and such displacement of the pin 88 causesthe pin to engage the ball valve 91 and displace it from its seat, asshown in Figure 9. '.Above the cam 97 the release bar has a notchor'recess 97 affording the clearance necessary to permit the valve 85 toseat when the trip'rod95 is in its lowermost-position. l

At its upper end, the trip rod 95 is rovided with a lateral extension 98a rture to slidably receive the plu er ro 55. The juncture of theplunger r0 and plunger 54 presents a shoulder 99 which, when the plungerrod is raised to its extreme upper position, is engageable with thelateral extension 98 of the trip rod 95 to raise the tri rod and causeit to unseat the valves. Ordinarily the trip rod is held in itslowermost and inactive position by means of a coil spring 100 encirclingthe plunger rod 55 and engaging the packing 58 at one end and thelateral extension 98 at its other end. A sleeve 101 loosely embraces theplunger rod 55 and is interposed between the plunger rod and the lowerportion of the spring 100 to prevent the spring from buckling. The upperend of this sleeve 101 is bevelled off as at.101 to facilitate thesliding of the sleeve past the convolutions of the spring.

As will be understood from Figures 8 and 9,

the lower portion of the trip rod completely obstructs or blocks theopening 96 when the trip rod is raised so as to prevent the oil fromflowing up into the housin 56. This obviates any possibilit of the oilleaking out when the jack is store The trip rod is provided with a lon'tudnal draining groove 94 which bridges t e wall of the opening 96 whenthe trip rod islowered and permits any oil that may have found its wayinto the housing 56 to drain back into the passage 71. There is notendency for the oil to flow through the o nin v96 into the housing 56except when t e va ves are tripped and the springs 23 or load on thejack are forcing the ack piston 12 downto move the oil quickly ack intothe reservoir and at such time the lower end of the draining groove 94is drawn up out of'the passage 71 and closed b the wall of the opening96 while the note 97" is .still within the confines of the opening 96and consequently the opening 96 is completely blocked as shown in Figure9.

With this construction, when the plunger 54 is moved downwardly in thebarrel 52, it forces the fluid, usually oil, down through the ports intothe passage 71. The pressure of the fluid and the force of the s ringseats the valve 85but the pressure 0 the fluid unseats valve 91 topermit the fluid expelled b the pump to pass from the passage 71 througthe port 79, passage 80, port 81, groove 82,

' and. passage 83 into the lower end of the jack ing the piston 12 upwarof the plunger 54, the sprin 92 and the pressure combine to seat the vave 91 but the succylinder 5 and beneath (piston 12, thus movly. On theupstroke tion induced. by the plunger 54 opens the valve 85 and drawsthe oil from the reservoir passage 71 past the valve 85 and up into the'ump barrel through the port 70.

' v When it is desired to lower the piston, the

operating rod 64 is ulled outwardly as far as it will move there yactuating the tri rod 95 and unseating the valves 85 and 91 w ereuponthe weight carried by the piston of the jack or the springs 23 or bothoperate to force the piston 12 down and to cause the After the piston 12of the jack has been I elevated as far as it may be, continued opera--tion of the pump will not resultin the buildin up of excessive pressuresin the jack cylin der ,because of. the provision of a minute ventingorifice in the inner cylinder 5 which permits theexcessive pressure topass into the reservoir 7 5" and thence back to the pump.

To facilitate reciprocation of the operating rod 64 it may be providedwith a transverse hand grip but where heavy loads are to be lifted'theoperating means of Figure 1 is preferably employed and as shown consistsof an operating lever 126 having one end bifurcated and fulcrumed as at127 on a link 128 pivotally supported as at 129 in a slot formed at theouter end of a laterally extending lug 130 integral with a head orcollar 131 replacing the guide 65 and shrunk or otherwise secured in theupper end of the handle section 59 and having an axial opening throughwhich the operating rod 64 slidably extends. The lever 126 is pivotallyconnected to the outer end of the rod 64 by means of a removable pivotpin 132 extending throu h transverse pivot openings provided in t elever and in the rod 64 and held against accidental displacement by acotter pin 133. This arrangement permits the operating lever to bereadily disconnected from the rod 64 and .folded with its link upagainst the handle section 59 when the jackis knocked down, asillustrated in dotted lines in Figure 1. To secure the parts in foldedposition a spring clip 134 is mounted on the handle section 59 and hasits spring jaws designed to embrace and hold the lever 126, asillustrated in Figure 4. This is of especial advantage in connectionwith the character of combined handle and housing used whose sectionsmay be disconnectedto permit the jackto be made into a compact bundleand-stored in the tool box, or under the seat, or the like.

The invention claimed is:

1. A hydraulic jack comprising hydraulically operable lift mechanism, amounting member connected thereto, a pump carried by the mountingmember, there being passages in the mounting member leading from thepump to the hydraulically operable lift mechanism, valve means in saidpassages constraining the pump, when operated, to elevate thehydraulically operable lift mecha- 65 ture.

nism, a trip cooperable with said valve means to permit thehydraulically operable lift mec anism to lower, a casing for the tripand pump, said mounting member having an openingthrough which the tripextends, said trip completely obstructing said opening when positionedto trip the valves, said trip having a drain groove bridging the wall ofsaid openin when the trip is in inoperative position an blocked by thewall of the openmg when the trip is in operative position.

2. A hydraulic jack comprising a hydraulically operable lift mechanism,a mounting member connected thereto, a pump carried by 5 the mountingmember, there being passages in the mounting member leading from thepump to the hydraulically operable lift mechanism, intake'anddischargecheck valves in -said passages forcausing the pump when '20operated to elevate the hydraulically oper able lift mechanism, saidmounting member having an opening on the side of the intake check valveremote from the pump, a trip for the valves extending through saidopening,

a casing for the pump and trip carried by the mounting member, said tripbeing effective to close said opening when in position to trip thevalves and permitting draining of the casing when in inoperative posi- 0tion.

3. A knock-down operating mechanism for use in swinging a swingablymounted pump of a hydraulic jack and reciprocating the plunger rodthereof and comprising a tubular handle connected to the pump and havinga detachable outer section, an operating element for the pump movablethrough the handle, a detachable connection between the operatingelement and the plunger rod releasable, only when the sections ofthe-handles' are detached, an operating lever fulcrumed on thedetachable handle section, a releasable connection between the operatinglever and the operating element, said operating lever being foldable upagainst the handle when disconnected from the operating element, andmeans for releasably securing the operating lever folded against thehandle.

4. A knock-down operating mechanism for reciprocating the plunger rod ofthe pump of a hydraulic jack and comprising a handle, an operatingelement for the pump associated with the handle, a link pivotallysupported on the handle and pivotally connected to the operating leverto provide a fulcrum therefor, a releasable connection between theoperating lever and the operating element whereby said operating levermay be folded up against the handle when disconnected from the operatingelement, and means for releasably securing the operating element foldedup against the'handle.

In witness whereof, I hereto afiix my signaiHARRY w. BoLEN's;

